For reasons of maintaining a sanitary environment for the manufacture of pharmaceutical products, processing and handling equipment have been traditionally made of stainless steel. As is well understood, stainless steel will not oxidize and may be cleaned repeatedly in an autoclave. Many pharmaceutical products, e.g. serums, vaccines, and other injectable medications are packaged in glass vials. The glass vials are typically sealed with a metal band holding an elastomeric membrane over the vial opening.
These glass vials are generally loaded onto stainless steel trays during the manufacturing process, e.g. for autoclaving, filling, or transporting. Depending on the stage of processing, the glass vials may be either empty or full when loaded onto trays. In all known tray loading machinery, the vials are pushed onto the trays causing the bottom of the vial to rub across the surface of the tray. It is well known that glass is very hard, on the order of 68-72 on the Rockwell C Hardness Scale. By comparison, stainless steel has a hardness of approximately 17 on the same scale, being much softer than glass. Therefore, rubbing glass on stainless steel will scratch the stainless steel surface and generate a fine particulate metallic dust. Federal Food And Drug Administration regulations prohibit any particulate in pharmaceutical clean environments as a potential source of contamination. With existing tray loading machinery this problem cannot be avoided and must be corrected by either periodically refinishing the tray surface or by replacing badly abraded trays. In addition to the danger of product contamination, tray remediation or replacement is expensive. In current pharmaceutical processing some equipment, e.g. handling trays, may be made of a plastic resin that can withstand the autoclaving process. Plastic resin will be readily scratched by abrasion with a glass vial being pushed over the plastic surface, in some cases producing unacceptable particulate.
An alternate type of equipment for loading parts into cartons or onto trays is known in the packaging industry. This loading equipment operates by engaging the bottle, box or other piece for packing from above, therefore exposing the top of the piece to contamination. Because of the potential for contamination, this equipment is not considered to be acceptable for use in loading pharmaceutical vials onto trays.